Artificial yarn producing apparatus



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c. PISTOR4 Er AL ARTIFICIALYARN PRODUCINGAPPARATUS Feb. 10, 1959 Filed Nov. 14, 1955 n' e L #EQ- J United dStates Patent-O r'ce ARTIFICIAL YARN PRODUCING APPARATUS Christel Pistor, Drexel Hill, and Henry J. McDermott,

Collingdale, Pa., assguors to American `Viscose Corporation, Philadelphia, Pa., a corporation ofv Delaware Application November 14, 195,5, Serial No. 546,403 6 Claims. (Cl. 1,8-8)

The present invention relates toa novel and improved apparatus for producing or spinning artificial yarns at high spinning speeds.

` In recent years, many new and improved high-speed methods and apparatus have been devised for producing artificial yarns such as viscose-type rayon wherein a viscose spinning solution, is extruded through a spinnerette to form filaments which are hardened by passing them through a suitableacid bath. The filaments are combined within the bath to form a yarn after which the yarn is stretched and twisted while it is still in a plastic state. The processed yarn is then collected in or on a suitable collecting unit.

One of the main difficulties encountered in developing the high-speed spinning systems was that known as acid starvation. The term acid starvation means that theyarn filaments, just after they issue from the spinnerette, were not receiving sufficient amounts of fresh non-contaminated coagulating acid due to the high speed extrusion of the filaments.v This condition is particularly prevalent in the production of tire cord wherein large bundles of filaments are extruded. It is very important that fresh acid be supplied to the filaments at the point of extrusion since an initial and adequate hardening or coagulation of the filaments must occur at this point to withstand the `stretching and other physical forces appliedto the filaments immediately after the filaments are extruded. To counteract this condition of acid starvation at the face of the spinnerette, it was decided that the coagulating bath should be made to flow rapidly in a path past the spinnerette facein a direction concurrent with that` of filament travel. The thought here was that fresh acid would be rapidly supplied across the spinnerette face. To carry out this idea, the filaments were spun into an elongated tube submerged in the coagulating bath and were drawn through the `tube by suitable godets. The acid bath flow within the bath was set upv so as to flow through the tube. With this arrangement, a continual fiow of coagulating bath passed over the spinnerette face and into the spinning tube in the direction of the moving filaments. The use of a spinning tube aids in setting up a rapid and accurately controlled acid ow.

This arrangement did help to alleviate somewhat the acid starvation condition adjacent the spinnerette; however, further improvement wasdesirable to provide spinning conditions wherein the acid starvation was substantially eliminated.

AdditionalA attempts were made to increase the acid flow into the tube by increasing the clearance between the inner wall of the tube mouth and the spinnerette periphery positioned within the tube mouth. It was ,y thought that such condition would allow a greater quantity of acid to enter the tube. The producers figured that a corresponding increase of acid iiow would also result across the face ofthe slpinnerette and into the tube- It .was found, however, that the acid tlowacress 2,872,701 Patented Feb.v 10, `*1959 the actual spinnerette face was actually decreased in this instance. The clearance mentioned above was also decreased in an attempt to increase the acid iiow through the tube. It was found that a corresponding increase of acid flow did occur across the spinneretteface and within the tube; however, there was not a sufiicient quantity of acid entering thevtube to adequately coagulate the filaments passing therethrough especially when tire cord was being spun. To date, no satisfactory ap-` paratus or method has been developed for actually increasing the acid flow across 4the spinnerette face and through the normally used spinning tubes while simultaneously supplying the tube with the required amount of coagulating solution especially when spinning heavy denier yarn such as tire cord.

It is therefore one object of our invention to provide a novel and improved high speed tube spinning apparatus for producing artificial yarns wherein the flow of the filament coagulating medium over the spinnerette face is of suicient velocity to continuously supply fresh acid in adequate amount to the filaments as they emerge at high speeds from the spinnerette. j

lt is another object of our invention to provide a novel and improved tube spinning apparatus for forming yarns wherein an increased acid ow is effected across the face of the spinnerette and wherein a sufficient quantity of the acid with adequate flow is continuously supplied through the spinning tube whereby the filaments may be properly coagulated as they issue from the spinnerette and as they pass through the tube.

Another object of the invention'is to provide a high speed tube spinning apparatus wherein a relatively quiescent area is provided in the acid ow over and adjacent the spinnerette face.

Other objects and advantages of our invention will become apparent vfrom av study of the following description and drawing wherein:

Figure l is aside' view partially sectioned of our novel and improved tube spinning apparatus for forming artificial yarns; and

Figure 2 is a View taken along the lines lI-II of Figure l.

Referring now to the drawing, our improved tube spinning apparatus comprises a container 1 which holds a quantity of a coagulating medium 3 such as a sulfuric acid of desired composition. The coagulating bath container 1 has suitable inlets and overflow units (not shown) whereby the level of the bath within the container may be held constant. The spinning solution from which the filaments 6, 6 are formed passes through v a conduit 8 which is pivotally mounted at a point outside of the container 1. One end of the conduit 8 fits within a terminal connector 11 which in turn is supported within a bracket 14 secured to a wall 17 of the container 1. To support the conduit S within the bracket 14, a bolt 19 extends through one of the bracket arms and is tightened against the terminal connector 11. With this arrangement, the conduit 8 may be swung into and out of the Vcoagulating bath by manual manipulation.

The filament-forming solution, such as viscose, is introduced into the terminal connector 11 and into the conduit 8 through a stationary supply pipe 22. The pipe 22 leads from a pump which receives the spinning solution from a filter unit connected with a main supply line for the spinning solution (none of these elements being shown).

A spinnerette 25 is connected to the opposite end of conduit 8 through a coupling 27 and the conduit connector 2,9. The spinning solution passes through the Supply pipe 22, into the terminalv connector 11, through 3 i I t the conduit 8 aud finally through the spinnerette 25 fro which the shaped filaments issue.

Extending through the wall 17 of the coagulating bath container 1 is a duct memberl 31whercin the duet is preferably of funnel-shape. The tapered mouth portion 33 of the funnel-shaped duet lies within the interior of the container 1 while the stem portion 35 of the funnelshaped duct member lies .generally externally of the bath container 1.

A second shorter duet member 37 wherein the duct is preferably of funnel-shape and of smaller diameter than the member 31 is positioned eoncentrieally within and terminates within thetapered mouth portion 33 of the duet member 31. The smaller or second duet member 37 which may be termed a small tube is permanently affixed in position and held in place within the first member' 31 by the retaining ribs 39, 39 of the open ribbed member 40 (Figure 2) affixed to the inner surface of the inner duct member 31. The ribs`39, 39 extend between the inner surface of the tapered mouth portion ol` duct member 31 and the periphery of the second member 37. Guiding bosses 42, 42 are affixed to the ribs 39, 39 and serve the purpose of guiding the spinnerette directly into the mouth of the second or smaller duct member 37 when the spinnerette 25 and conduit 8 are swiveled into the coagulating bath to assume their lowermost position.

A spinning tube 45 of larger diameter than the duet 37 is positioned Within the stern portion 35 of the funnelshaped conduit 31. A sealing ring 47 of suitable composition is provided in the indent 49 of the conduit 31 to prevent coagulating liquid from seeping out around the periphery of the tube 45. l

In operation', the conduit 8 and the spinnerette 25 secured thereto are lowered into the coagulating bath 3. The guiding bosses 42, 42 on the supporting ribs 39, 39 of ribbed member 40 guide the spinnerette into place directly within the mouth of the smaller or second duct member 37. Spinning solution, lsuch as viscose, is then permitted to fiow through the supply pipe 22 from which it passes into the terminal connector 11 and into the eonduit S. After traveling through the conduit 8, the spinning solution passes through the spinnerette 25 to form the filaments 6, 6. The filaments then pass into and through the second or smaller duct 37.

As seen in the drawing, acid is permitted to enter within the smaller or inner duct 37 as indicated by the arrows. The flow of acid within the duet 37 is created both by the acid flow as set up within the container and by the rictional contact or drag set up between the traveling filaments and the coagulating medium.

The flow of the medium over the face of the spinnerette and through the duct 37 is substantially and effectively stepped up or increased because of the combined features of the small degree of clearance between the spinnerette periphery and the inner wall of the duct 37 and the small diameter of the duet adjacent its discharge end. This flow ratio may be varied as desired by changing the clearance and the diameter of the duet 37 at its discharge end. With this arrangement, fresh coagulating medium is continuously supplied in adequate amounts and with sufficient high velocity across the spinnerette plate to provide sufficient coagulating potential for the rapidly issuing filaments. With this fresh supply of coagulating liquid being continuously supplied at a rapid rate across the spinnerette face, extremely high speed filament extrusion may be effected.

After the filaments 6, 6 emerge from the duct member 37, they pass into and through the spinning tube 45. As mentioned in the opening paragraphs of our description, we stated that although adequate rates of tiow of the acid could be obtained across the spinnerette face by reducing the size of a spinning tube mouth, we also mentioned that an adequate supply of acid could not be received into the spinning tube to thoroughly coagulate the 4 filaments passing therethrough. The same holds true in the present instance. Although a sufiieient flow is provided across the spinnerette face, the amount of acid passing through the duct and into the tube 45 is not sufficient to supply the acid required by the main spinning tube 45 for completing the coagulation of the filaments passing therethrough. To supplement the amount received by the spinning tube 45 from the duct 37, acid also flows from the container 1 around the ribs 39, 39 and into and through the annular channel 55 formed between the periphery of the small duct 37 and the inner wall of the tapered mouth portion 33 of the funnel-shaped duet member 31. The acid entering the channel 55 ows over the periphery of the smaller duct member 37 and is combined with the acid emerging from the discharge end of the smaller duet 37. An acid rate of fiow similar to that set up within the duct member 37 is set up within the channel 55. With the combined streams passing into and through the tube 45, there is present within the tube 45 an adequate supply of acid to thoroughly complete the coagulation of the filaments 6, 6 passing therethrough.

After the filaments leavethe tube 45, they are further processed and collected in or on a suitable collecting unit.

As seen from the above description, we have provided an apparatus for forming artificial yarn wherein the filament extrusion may be conducted at extremely fast speeds. Another advantage is that a quiescent area is provided in the acid fiow immediately adjacent the spinnerette face since the rate of travel of the acid at this point approaches the rate of filament travel. Turbulence at this point, of course, creates undesirable extrusion or spinning conditions since the filaments may be ruptured by the turbulent flow. Also, the filaments will group into a smaller bundle after emerging from the spinnerette since the duct 37 is of generally small diameter. Drag between the filaments and the bath is thereby reduced.

While preferred embodiments of the invention have been shown and,described, it is to be understood that changes and variations may be made without departing from the spirit and scope of the invention as defined in the appended claims.`

We claim:

l. Apparatus for spinning filaments by the wet-spinning process comprising a coagulating bath container, a supply conduit for the spinning solution which conduit is pivotally mounted externally of the coagulating bath container whereby the conduit is swingable into and out of the container, a spinnerette secured to the free end of the conduit, afirst duet member extending through one wall of the container, a smaller duct member of shorter length and of smaller diameter than the tirst duct member positioned concentrically within and terminating at a point along the length of the first duet but prior to the discharge end of the first duet member whereby a channel is formed between the inner wall of the first duct member and the periphery of the smaller duet member, the mouth of said smaller duet being of slightly larger diameter than that of the spinneret for receiving the spinnerette when the spinnerette and its supporting conduit are swung into their lowermost position within the bath, means extending from the first duet member for supporting the smaller duet in place, and a spinning tube of larger diameter than the smaller duct positioned within the discharge end of the first duet member which tube extends externally of the duct with the mouth of the tube spaced apart from thc discharge end of the smaller duet whereby the filaments issuing from the spinnerette will pass through the smaller duct and into the spinning tube along with the streams of coagulating bath which flow from theeontainer through the channeland through the smaller duct.

2. Apparatus for spinning filaments by the wet-spinning process accordingto claim 1'comprisingA supporting means axed to the smaller duct member for supporting the smaller duct in place within the first duct member.

3. Apparatus for spinning laments by the wet-spinning process according to claim 2 comprising guiding means axed to and extending from the supporting means4 for the smaller duct which means guide the spinnerette into position directly within the mouth of the smaller duct.

4. Apparatus for spinning laments by the wet-spinning process according to claim 2 wherein the supporting means comprises an open ribbed member axed to the periphery of the smaller duct wherein the ribs extend to and contact the inner surface of the rst duct.

5. Apparatus for spinning laments by the wet-spinning process according to claim 3 wherein the guiding means for properly positioning the spinnerette within the mouth of the first duct comprise bosses which extend from the supporting means.

6. Apparatus for spinning laments by the wet-spinning process comprising a coagulating bath container, a supply conduit for the spinning solution which conduit is pivotally mounted externally of the coagulating bath container whereby the conduit is swingable into and out of the container, a spinnerette secured to the free end of the conduit, a irst funnel-shaped duct member extending through one wall of the container with the tapered mouth portion of the funnel-shaped duct member positioned within the container and with the stem portion of the duct member extending externally of the container, a smaller funnel-shaped duct member of shorter length and of smaller diameter than the first duct member positioned concentrically within and terminating at a point along the tapered mouth portion of the rst funnelshaped duct member whereby an annular channel is formed between the wall of the tapered mouth portion of the rst duct member and the periphery of the smaller duct, the mouth of said smaller duct receiving the spinnerette when the spinnerette and its supporting conduit are swung into their lowermost position within the bath, said smaller duct having a substantially smooth even periphery which gradually decreases in diameter as it extends away from the face of the spinnerette a supporting open ribbed member affixed to the smaller duct member for supporting the smaller duct in position wherein the ribs extend to and contact the inner wall of the rst duct, guiding means extending from the ribs for guiding the face of the spinnerette into position directly within the mouth of the smaller duct, and a spinning tube of larger diameter than the smaller duct positioned within the stem portion of the trst duct which tube extends externally of the rst duct with the mouth of the tube spaced apart from the discharge end of the smaller duct whereby the laments issuing from the spinnerette will pass through the second duct and into the spinning tube along with the streams of coagulating bath which flow from the container through the' annular channel and through the smaller duct.

References Cited in the tile of this patent UNITED STATES PATENTS 2,289,657 Kneke c July 14, 1942 2,416,291 Detwiler Feb. 25, 1947 2,690,663 McDermott Oct. 5, 1954 2,696,637 McDermott Dec. 14, 1954 2,711,559 Lynch et al. .lune 28, 1955 UNITED STATES PATENT OFFICE CERTIFICATE 0F CORRECTION Patent NO. 2,872,701 February lO, 1959 Christel gister et s1.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 3', before line 34,' insert the following paragraph:

-f For all practical purposes, the duct 3l and thel tube I5 rmay be considered as' a single spinning tube,v n.,

Signed `and sealed thi's`l6th day of June 1959.

(SEAL) Attest:

KARL H. AXLINE Attesting Officer ROBERT C. WATSON Commissioner of Patents 

